Meat analogs containing fibrous, vegetable proteinaceous materials (often referred to as textured vegetable proteins) are used as meat substitutes. Meat analogs may be prepared by combining the textured vegetable protein with an edible binder, fats, flavoring agents, etc. and fabricated so as to resemble natural meat cuts. Hydrated, textured vegetable proteins are also used as proteinaceous diluents or extenders in comminuted meat products.
Spinning and extrusion processes are the predominant source of textured vegetable proteins which are used for human consumption. The spinning processes are analogous to the manufacture of synthetic textiles. In the spinning processes, aqueous vegetable protein isolate solutions are typically passed through a spinnerette into a coagulating bath so as to form filaments which are then stretched and collected as filaments or a tow upon collecting reels (e.g., see U.S. Pat. No. 2,682,466). The textured vegetable protein extrusion processes are similar to those processes which are conventionally used to manufacture extruded cereal, snack and plastic products. A typical extrusion process entails forcing a protein-water mix through an extrusion barrel under elevated temperature and pressure so as to form a molten mass, and extruding the molten mass through a die orifice into a zone of reduced temperature and pressure to solidify the cooked vegetable protein mass.
When natural meat textures and appearances are an important criteria, the spun protein fibers are recognized by many as best suited. Meat analogs closely resembling the appearance of diced ham and chicken cuts, breakfast slices, links and sausages have been produced on a commercial basis with spun fibers. Unfortunately, the adaptability and compatibility of the spun protein fibers to a broad spectrum of products, as required by the meat industry and the consuming public, is limited by certain inherent physical and chemical deficiencies of spun fibers. Moreover, complex purification and recovery processes in combination with different fabrication techniques are often needed in order to produce satisfactory meat analogs from these spun fibers. These factors, plus others, generally contribute to a high-cost meat analog which frustrates the low-cost meat replacement objective.
Although the protein extrudates are considerably less expensive to produce and convert to a meat analog, they have limited utility as a meat replacement. These protein extrudates possess several inherent deficiencies which have seriously limited their use as a spun filament protein substitute. Unlike the spun filament protein products, the extruded vegetable proteins typically fail to possess a fibrous meat-like structure sufficiently comparable in character to the meat-like texture normally associated with natural meat cuts. Consequently, the protein extrudates are most frequently used as a partial replacement or extender in ground meat products such as chili, meat patties, meat loaf, stews, casseroles, etc. For meat analogs wherein a fibrous meat-like appearance, texture, taste, flavor, mouth-feel, cooking characteristics, etc. are an important criteria (e.g., diced meat analogs resembling natural or diced meat cuts, sea foods, sausages, etc.), the protein extrudates leave much to be desired.
Numerous alternative methods and variations for producing textured vegetable proteins and meat analogs have been proposed. Illustrative thereof are U.S. Pat. Nos. 3,108,873 by J. R. Durst; 3,886,299 by Feldbrugge et al.; 2,802,737 by Anson et al.; 3,886,298 by Hayes et al.; 3,814,823 by Yang et al.; 3,935,319 by Norman Howard; Re 27,790 by Rusoff et al.; 3,904,769 by Sair et al.; 3,765,902 by Wayne Charter; Canadian Patent No. 978,414 by Oborsh et al.; Japanese Publication No. NS 20361/72 by K. K. Kuraray; U.S. Published Patent Application No. B 478,759 by Balaz et al.; U.S. Pat. Nos. 3,891,774 by Baker et al.; 3,719,498 by Leidy et al.; 3,736,148 by Morris H. Katz; 3,900,576 by Arthur A. Schultz; and 3,836,678 by Leidy et al.